This invention relates to the utilisation of wind energy for the purpose of generating mechanical energy which can be used directly to drive machines or can be converted to other forms of energy such as electrical energy.
Wind energy is a theoretically attractive source of man's energy requirements because the wind is universal and free and because it occupies a high position in the chain of energy conversion processes that start with the arrival of the sun's rays on the earth.
Although it has been exploited industrially for millenia, wind energy suffers from several disadvantages in relation to current-day patterns of energy requirements. Although the wind possesses vast quantities of energy, this energy is present in a relatively attenuated form and mechanically large devices, extracting energy over a correspondingly large surface, are required if meaningful quantities of energy are to be obtained from it. Further, it is sporadic in nature, and over large parts of the earth's surface is subject to a cyclical pattern in which the wind rises during the sunlight hours and subsides in the evening. Since the inertia of most wind-driven devices is substantial, it is often thought that low-speed winds, such as occur in the early and late sunrise hours before and after the main hours of wind, are not useful for industrial purposes. Moreover, being highly directional, the wind is inherently unsuitable for driving large bodies since the orientation of these bodies must normally change with the wind if they are to operate efficiently.